The Qianjiangping landslide occurred after the first impoundment of the Three Gorges Reservoir in July 2003. Field investigation revealed that failure occurred when the reservoir reached 135 m, but the stability of the affected slope was already reduced by pre-existing bedding-plane shears, quarrying of mudstone from the landslide toe, and previous heavy rain. A possible explanation of the rapid and long runout mechanism of the landslide is that movement on a bedding-plane shear ruptured the calcite cement and rapidly reduced the sandstone strength to residual shear strength.

SUMMARYA simplified method of numerical analysis based on elasticity theory has been developed for the analysis of axially and laterally loaded piled raft foundations embedded in non-homogeneous soils and incorporated into a computer program ''PRAB''. In this method, a hybrid model is employed in which the flexible raft is modelled as thin plates and the piles as elastic beams and the soil is treated as springs. The interactions between structural members, pile-soil-pile, pile-soil-raft and raft-soil-raft interactions, are approximated based on Mindlin's solutions for both vertical and lateral forces with consideration of non-homogeneous soils. The validity of the proposed method is verified through comparisons with some published solutions for single piles, pile groups and capped pile groups in non-homogeneous soils. Thereafter, the solutions from this approach for the analysis of axially and laterally loaded 4-pile pile groups and 4-pile piled rafts embedded in finite homogeneous and non-homogeneous soil layers are compared with those from threedimensional finite element analysis. Good agreement between the present approach and the more rigorous finite element approach is demonstrated.

SUMMARYA simplified method of numerical analysis has been developed to estimate the deformation and load distribution of piled raft foundations subjected to ground movements induced by tunnelling and incorporated into a computer program 'PRAB'. In this method, a hybrid model is employed in which the flexible raft is modelled as thin plates, the piles as elastic beams, and the soil is treated as interactive springs. The interactions between structural members, pile-soil-pile, pile-soil-raft and raft-soil-raft interactions, are modelled based on Mindlin's solutions for both vertical and lateral forces. The validity of the proposed method is verified through comparisons with some published solutions for single piles and pile groups subjected to ground movements induced by tunnelling. Thereafter, the solutions from this approach for the analysis of a pile group and a piled raft subjected to ground movements induced by tunnelling are compared with those from three-dimensional finite difference program. Good agreements between these solutions are demonstrated. The method is then used for a parametric study of single piles, pile groups and piled rafts subjected to ground movements induced by tunnelling.

SUMMARYA simplified method of numerical analysis has been developed to estimate the deformation and load distribution of piled raft foundations subjected to vertical, lateral, and moment loads, using a hybrid model in which the flexible raft is modelled as thin plates and the piles as elastic beams and the soil is treated as springs. Both the vertical and lateral resistances of the piles as well as the raft base are incorporated into the model. Pile-soil-pile, pile-soil-raft and raft-soil-raft interactions are taken into account based on Mindlin's solutions for both vertical and lateral forces. The validity of the proposed method is verified through comparisons with several existing methods for single piles, pile groups and piled rafts. Workable design charts are given for the estimation of the lateral displacement and the load distribution of piled rafts from the stiffnesses of the raft alone and the pile group alone. Additionally, parametric studies were carried out concerning batter pile foundations. It was found that the use of batter piles can efficiently improve the deformation characteristics of pile foundations subjected to lateral loads.

A series of static loading tests were conducted vertically and horizontally on piled raft models and their components (single piles and rafts alone) on sand by using a geotechnical centrifuge. Much focus was placed on the load-displacement relationship and the load sharing between the piles and the raft in the piled raft system. Effects of the rigidity at pile head connection on the piled raft behavior were also examined. This paper provides basic information on the performance of piled raft foundations subjected to horizontal loads. Principal findings from the present study are: 1) The stiffness and the resistance of the single pile in piled raft foundations are different from those observed in the isolated single piles of the same size, due to the difference in the confining stress condition around the piles; 2) Piles play important roles in increasing horizontal ultimate resistance of piled raft foundations; 3) The initial horizontal stiffness of a piled raft is not always higher than that of a raft (alone) as the piles reduce the contact pressure between raft and soil, and hence the stiffness of the upper soils; 4) Higher horizontal load is transferred to the piles in the piled raft with rigid pile head connection, which leads to higher initial horizontal stiffness compared with that in the piled raft with hinged pile head connection; 5) The proportion of vertical load carried by the piles in a piled raft remains largely unchanged during horizontal loading, while the proportion of horizontal load carried by the piles increases as the horizontal displacement increases.

This paper employs a simplified analytical method to investigate the influence of reaction piles on the load-displacement behaviour of the test pile in static load testing. A parametric study is conducted to examine the effects of factors such as pile spacing ratio, pile slenderness ratio and pile soil stiffness ratio. Several soil profiles are considered in this study.The parametric study also includes the cases of static load testing in lateral direction. The correction factors for the initial pile head stiffness obtained from static pile load tests with the use of reaction piles are given in charts. Furthermore, analyses of centrifuge modelling of axially loaded piles are carried out using the simplified analytical method. Good agreements between the test results and the analysis results are demonstrated, and the applicability of the correction factors is verified.

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Neuromuscular-blocking effects on the diaphragm can be recorded in vivo. According to direct contractile force measurement, the diaphragm is more resistant to non-depolarizing neuromuscular-blocking drugs than the tibialis anterior muscle.